Pattern guards

Yitzchak Gale gale at
Tue Oct 3 04:25:16 EDT 2006

Ross Paterson wrote:

> Yitzchak Gale wrote:

>> Maybe monads quit on failure and
>> continue on success. We want the opposite
>> semantics for guards, pattern matching, and
>> the like.

> And that's what mplus does.

>> In particular, your identity... is not true...

Oops, yes it is, sorry.

You are using mplus as the "dual" of
(<<) rather than dualiing the monad.


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